Efficient microwave assisted access to chiral O-(α-protected-aminoacyl)steroids
摘要:
Chiral O-(alpha-protected-amino acyl)steroids 4a-f, 6a-b, 8 and 4a+4d and O-(alpha-protected-dipeptidoyl) steroids 12a,b are conveniently prepared under microwave irradiation in isolated yields of 65-96%, with complete chirality retention. The reaction utilized readily available N-(Z-alpha-aminoacyl)benzotriazoles 2a-f and Z-dipeptidoylbenzotriazole 11, with naturally occurring steroidal alcohols 3,5,7,9. (c) 2006 Elsevier Inc. All rights reserved.